U.S. patent number 4,445,620 [Application Number 06/380,517] was granted by the patent office on 1984-05-01 for tamper-proof closure for container.
This patent grant is currently assigned to Minnesota Mining and Manufacturing Company. Invention is credited to Wilfred R. Brochman, Richard A. Patterson.
United States Patent |
4,445,620 |
Brochman , et al. |
May 1, 1984 |
Tamper-proof closure for container
Abstract
A tape closure comprising a two-tape closure system for a pour
opening in a container wherein the pull tab for the closure is
secured to the container end by a rupturable nonresealable
holddown.
Inventors: |
Brochman; Wilfred R. (Oakdale,
MN), Patterson; Richard A. (Woodbury, MN) |
Assignee: |
Minnesota Mining and Manufacturing
Company (St. Paul, MN)
|
Family
ID: |
23501481 |
Appl.
No.: |
06/380,517 |
Filed: |
May 21, 1982 |
Current U.S.
Class: |
220/271;
220/260 |
Current CPC
Class: |
B65D
17/505 (20130101); B65D 2517/0082 (20130101); B65D
2517/5035 (20130101); B65D 2517/0013 (20130101); B65D
2517/0094 (20130101); B65D 2517/5083 (20130101) |
Current International
Class: |
B65D
17/00 (20060101); B65D 17/50 (20060101); B65D
017/34 () |
Field of
Search: |
;220/260,270,271,359 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Hall; George T.
Attorney, Agent or Firm: Sell; Donald M. Smith; James A.
Barnes; John C.
Claims
We claim:
1. A container end assembly comprising:
a container end having a preformed pour opening, an interior and
exterior surface, and an easy-opening closure system covering said
pour opening comprising:
an interior tape having an adhesive on one surface adhered to the
interior surface of the container end and covering said pour
opening,
an exterior tape covering said pour opening and adhered to said
interior tape in the area of said pour opening and being adhered to
the exterior surface circumjacent said pour opening,
a pull tab secured to said exterior tape at one end thereof which
extends over said exterior tape, and
rupturable means for holding said pull tab to the exterior tape to
define a tamper-proof seal for the pull tab.
2. A container end assembly according to claim 1 wherein said
exterior tape has a vent hole formed therein in the area of the
pour opening and said pull tab is bonded to the interior tape
through said vent hole intermediate said one end and said
rupturable means.
3. A container end assembly comprising:
a container end having a preformed pour opening, an interior and
exterior surface, and an easy-opening closure system covering said
pour opening comprising:
an interior tape having an adhesive on one surface adhered to the
interior surface of the container end and covering said pour
opening,
an exterior tape covering said pour opening and adhered to said
interior tape in the area of said pour opening and being adhered to
the exterior surface circumjacent said pour opening,
a pull tab secured to said exterior tape at one end thereof which
extends over said exterior tape, and
rupturable means for holding said pull tab to the exterior tape to
define a tamper-proof seal for the pull tab, said rupturable means
comprising a folded end of said exterior tape forming a narrow band
which is firmly bonded to said pull tab and wherein said band is
joined to said exterior tape by a weakened fold line.
4. A container end assembly comprising:
a container end having a preformed pour opening, an interior and
exterior surface, and an easy-opening closure system covering said
pour opening comprising:
an interior tape having an adhesive on one surface adhered to the
interior surface of the container end and covering said pour
opening,
an exterior tape covering said pour opening and adhered to said
interior tape in the area of said pour opening and being adhered to
the exterior surface circumjacent said pour opening,
a pull tab secured to said exterior tape at one end thereof which
extends over said exterior tape, and
rupturable means for holding said pull tab to the exterior tape to
define a tamper-proof seal for the pull tab, said rupturable means
comprising a length of said exterior tape opposite said one end
which is bonded to said pull tab and which is joined to said
exterior tape along a weakened line.
Description
DESCRIPTION
1. Technical Field
This invention relates to an improvement in easy-openable tape
closure systems for containers, and in one aspect, to a
tamper-proof closure to permit visible inspection of the seal.
2. Background Art
Easy-open tape closure for containers are known utilizing a
two-tape closure system for a pour hole in the container end
including the combination of an interior sheet material covering
the pour hole on the inner side of the container end, an exterior
tape covering the pour opening on the exterior surface of the
container end, and a pull tab extending over the exterior tape to
peel the tape and open the pour opening. An improved structure is
disclosed in U.S. Pat. No. 4,405,056, issued Sept. 20, 1983 and
assigned to the common assignee, including a vent opening in the
exterior tape in the area of the pour opening which is opened by
the pull tab which is bonded to the interior tape through the vent
opening. The prior tape closure systems did not provide a
non-resealable tab affording an indication of any tampering with
the vent seal which could be readily detectable by the observer.
Thus, it is the purpose of this invention to provide a tape closure
for a container end which incorporates a seal for the pull tab of
the closure such that one can readily inspect the closure to
determine whether or not the closure has been ruptured or
opened.
DISCLOSURE OF INVENTION
The present invention provides an easy-open closure for containers
having a panel with a preformed pour opening. The easy-open tape
closure system comprises an interior sheet material which covers
the interior surface of the container end and which is firmly
adhered to the end circumjacent the pour opening, an exterior
flexible tape adhered to the end portion of the container on the
exterior surface about the pour opening and firmly adhered to the
interior tape in the area of the pour opening and being folded back
upon itself on each end of the pour opening for forming a grip or
pull tab and hold-down means therefor. The grip tab extends from
one marginal edge of the pour opening across the exterior tape and
is secured by a rupturable hold-down means at the opposite end of
the pour opening. An example of the rupturable hold-down means is
an upturned end of the exterior tape to which the grip tab end is
bonded. The end of the exterior tape is weakened as by scoring or
perforations along the fold line to rupture upon lifting force
being applied to the grip tab to lift the same from the exterior
tape.
BRIEF DESCRIPTION OF THE DRAWINGS
This invention will be described in greater detail hereinafter with
reference to the accompanying drawings wherein:
FIG. 1 is a plan view of a container end assembly constructed in
accordance with the present invention;
FIG. 2 is an enlarged sectional view taken along the line 2--2 of
FIG. 1;
FIG. 3 is a sectional view according to FIG. 2, showing the pull
tab being lifted from the container end panel and the rupture of
the seal for the grip tab;
FIG. 4 is an enlarged cross-sectional view showing the next step of
the opening of the container showing the venting of the container;
and
FIG. 5 is a detailed cross-sectional view showing the pour hole
opened with the closure tapes folded back over the container
panel.
BEST MODE FOR CARRYING OUT THE INVENTION
The container end assembly 10 of the present invention is
illustrated as a can end 11 formed of flexible metallic sheet
material by a stamping operation, and comprises a generally
circular, flat disc of material formed with a circular chime 12 and
a preformed U-shaped pour opening 14. The closure for the assembly
comprises an interior sheet material 15 which comprises a backing
member 16 which is firmly adhered to the underside or interior
surface of the can end 11 by means of an adhesive layer 17. The
interior sheet material 15 is adhered about the pour opening 14. In
the area of the pour opening the interior sheet material is
adhesively secured to an exterior tape material 20. The exterior
tape material 20 comprises a flexible backing to which is coated an
adhesive layer. The exterior tape material has one portion 21
adhesively secured by the adhesive layer 22 to the exterior surface
of the can end 11 around the pour opening 14 and to a tongue-like
member 23 which projects into the pour opening from one end
thereof. In the area of the pour opening the portion 21 of the
exterior tape 20 is firmly adhered to the interior tape 15. Portion
21 of the exterior tape is also formed with a vent opening 24 in
the area of a pour opening exposing the adhesive 17 of the interior
tape 15 at the vent opening.
The exterior tape is folded at one end of the pour opening adjacent
the tongue along a weakened line formed by scoring or by
perforations 25 in the tape. The folded tape defines rupturable
hold-down means for the free end of a grip tab. The hold-down means
comprises a short band 28 exposing a band of the adhesive 22. The
portion 21 is joined to the pull tab portion 26 of the exterior
tape at a fold line 27. The pull tab portion formed onto the
exterior tape portion 21 near the fold line 27 extends back across
the tape portion 21. This pull tab portion 26 covers the vent
opening 24 and is sealed to the interior tape 15 through the vent
hole 24 and it extends on over the exterior tape portion 21 and
over the band 28 where again the pull tab portion 26 is securely
and firmly sealed to the band 28 by the exposed adhesive 22. The
end 30 of the pull tab 26 is positioned beyond the band 28 a short
distance and is formed with surface irregularities such as
embossments 29 to permit the consumer to grasp the end of the grip
tab portion 26 and open the closure assembly.
Alternatively, the rupturable hold-down for the grip tab may be a
spot or strip of low strength rupturable thermoplastic adhesive
placed between the grip tab and the exterior tab.
Sealing the pull tab portion 26 at the vent opening 24 and onto the
band 28 of the external sealing tape portion 21 makes the pull tab
lie flat against the container end and its seal to the band 28
forms a tamper-proof seal for the closure. In the event that the
pull tab is tampered with or lifted sufficient such that the vent
opening, for example, could be opened the band 28 will be torn free
from the sealing tape 21 because of the perforations 25 along the
fold line of the tape, and the pull tab will not be resealable as
the band 28 will not be sealed or sealable back down to the
exterior tape portion 21.
The closure system illustrated is opened by the consumer gripping
the end 30 of the pull tab portion 26 and lifting it from the can
end 11 with sufficient force to rupture the tape between the
perforations 25 joining the band 28 to the exterior tape portion 21
as illustrated in FIG. 3. The continued lifting of the pull tab 26
then vents the container by separating the pull tab portion 26 from
the vent opening tearing the interior tape 15 at the vent opening
24 where the pull tab 26 is tightly bonded to the interior tape 15
by the adhesive 17. This is illustrated in FIG. 4. The venting of
the can is essential when the container contains a gas-containing
beverage and pressure can build up within the container.
Continued pulling of the pull tab then begins to unfold the
exterior tape at fold line 27, and a peeling of the exterior tape
portion 21 and the adhesive 22 from the external surface of the
can. As the peeling reaches the edge of the pour opening 14 the
interior tape material in the area of the opening 14 remains
adhered to the exterior tape portion 21 and tears cleanly out of
the opening 14 to provide access to the contents of the container.
The continued lifting of the pull tab 26 and the peeling of the
exterior tape portion 21 causes the tongue-like portion 23 to lift
along with the tapes between which it is sandwiched. The presence
of the tongue provides means for securing the interior and exterior
tapes to the container to discourage or prevent complete removal of
the tapes when opening the container, and the tongue-like portion
23 will take a permanent set and hold the tape clear of the pour
opening 14 such that it will not be in the way or objectionable
when pouring or drinking the contents of the container through the
pour opening. The use of this tongue-like member is disclosed in
U.S. Pat. No. 4,108,330, assigned to the assignee of this
application.
Constructions for the interior and exterior tape sheet material and
backing together with the adhesive useable therewith, are disclosed
in copending application Ser. No. 264,657, filed May 18, 1981, in
the name of W. R. Brochman, and assigned to the assignee of this
application, now U.S. Pat. No. 4,378,074, the disclosure of which
is specifically incorporated herein by reference.
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